Type species:
undulosa WalkerThis genus was
reviewed by Lajonquière (1975) who recognised four largely allopatric species in
mainland Asia that did not extend south of the Himalayan region and northern
Vietnam. Grunberg (1923) included the Sunda Islands in his distribution for
undulosa but this may refer to the species described here, representing a major
disjunction from the rest of the generic range.

The forewings of
all species are fasciated (double post- and antemedials) with pale lines on
dark blackish brown or brown, and are often somewhat translucent. Females are
larger than males, with deeper wings and less translucence. The venation is
unusual in that R4 is associated with the R2+3 system rather than with R5 + M1
(Figure 2).

The male
antennae are bipectinate, distinctly more broadly so over the basal quarter. In
the female pectinations are narrower and more even.

The male
genitalia have a well developed cubile, reduced, unequally bifid valves, a pair
of setose socii from the tegumen, and a short, flexed aedeagus with a group of
terminal spines; the vesica is unornamented.

The larva of
undulosa was described by Gardner (1941). The prothorax has two strong lateral
protruberances on each side, the lower one the longer. There are distinct
lateral protruberances on the body segments, being diffuse tufts of fine and
hastate/spatulate setae, those of the thorax black. The mesothorax and metathorax have small
transverse groups of moderately black setae, together with pale hastate setae.
The upper surface is partly nude, but abdominal terga have pale setae in two or
three transverse tufts on each segment. There are no distinct dorsal verrucae.
The head is blackish with pale marks, the body skin black, variegated paler; the
hair is predominantly olive green. The host in India was Quercus (Fagaceae).